* gensupport.c: Include hashtab.h.

	(insn_elision, condition_table, hash_c_test, cmp_c_test,
	maybe_eval_c_test): New routines and data structures to
	support insn elision.
	(init_md_reader): Read and initialize the condition_table.
	(read_md_rtx): Discard insn patterns whose C test is provably
	always false.
	* gensupport.h: Declare new functions and data structures.

	* genconditions.c, dummy-conditions.c: New files.
	* Makefile.in: Build genconditions; run it to construct
	insn-conditions.c; build that and link it into most gen*
	programs.
	(HOST_SUPPORT, HOST_EARLY_SUPPORT): New variables.
	(GEN): Delete, unused.
	(STAGESTUFF): Update.

	* gencodes.c: (gen_insn): #define CODE_FOR_xxx equal to
	CODE_FOR_nothing for all elided patterns.
	(main): Tweaked to support this.
	* genflags.c (gen_proto): Emit a static inline generator
	function here for all elided patterns, which simply returns
	NULL_RTX.
	(gen_insn): Do not define HAVE_xxx for elided patterns.
	(main): Tweaked to support this.  No need to forward-declare
	struct rtx_def.
	* genrecog.c: Do not bother emitting the C test if it's known
	to be true at compile time.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@55839 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 36 insertions, 0 deletions

diff --git a/gcc/gensupport.h b/gcc/gensupport.h
index bac804b22a6..8dbd0b70ea9 100644
--- a/gcc/gensupport.h
+++ b/gcc/gensupport.h
@@ -18,6 +18,9 @@ along with GCC; see the file COPYING.  If not, write to the Free
 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 02111-1307, USA.  */
 
+#ifndef GCC_GENSUPPORT_H
+#define GCC_GENSUPPORT_H
+
 struct obstack;
 extern struct obstack *rtl_obstack;
 
@@ -28,6 +31,39 @@ extern rtx read_md_rtx		PARAMS ((int *, int *));
 extern void message_with_line	PARAMS ((int, const char *, ...))
      ATTRIBUTE_PRINTF_2;
 
+/* Set this to 0 to disable automatic elision of insn patterns which
+   can never be used in this configuration.  See genconditions.c.
+   Must be set before calling init_md_reader.  */
+extern int insn_elision;
+
+/* If this is 1, the insn elision table doesn't even exist yet;
+   maybe_eval_c_test will always return -1.  This is distinct from
+   insn_elision because genflags and gencodes need to see all the
+   patterns, but treat elided patterns differently.  */
+extern const int insn_elision_unavailable;
+
+/* If the C test passed as the argument can be evaluated at compile
+   time, return its truth value; else return -1.  The test must have
+   appeared somewhere in the machine description when genconditions
+   was run.  */
+extern int maybe_eval_c_test	PARAMS ((const char *));
+
+/* This table should not be accessed directly; use maybe_eval_c_test.  */
+struct c_test
+{
+  const char *expr;
+  int value;
+};
+
+extern const struct c_test insn_conditions[];
+extern const size_t n_insn_conditions;
+
+#ifdef __HASHTAB_H__
+extern hashval_t hash_c_test PARAMS ((const PTR));
+extern int cmp_c_test PARAMS ((const PTR, const PTR));
+#endif
+
 extern int n_comma_elts		PARAMS ((const char *));
 extern const char *scan_comma_elt PARAMS ((const char **));
 
+#endif /* GCC_GENSUPPORT_H */